Summary

American Airlines operates several hub airport bases today – including Dallas Fort Worth, Charlotte, Chicago O'Hare, Philadelphia, New York, JFK, and Los Angeles. There have been several others in the past that have since diminished in importance. These include Nashville International Airport (BNA), St Louis Lambert International Airport (STL), and Raleigh-Durham International Airport (RDU). Pittsburgh International Airport (PIT) and Las Vegas (LAS) were also both hubs that came via US Airways.

We take a look in this article at St Louis Lambert International Airport. This was acquired from TWA in 2001 as its major hub, but it was not as necessary for American Airlines. With traffic switched to other hubs and declining traffic following 9/11, St Louis was finally closed as a hub in 2009.

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American Airlines and St Louis Lambert International Airport

has a long and historic association with St. Louis. Long before it developed as a major international airport, it was a pioneering destination for early flights.

Charles Lindberg is credited with flying the first American Airlines flight from St. Louis in April 1926. This was a mail service from St. Louis to Chicago. Mail was the main business in these early days, with passenger service really expanding after the introduction of the Douglas DC-3 in the 1930s.

American has a long history.

St Louis as a TWA hub

American Airlines continued to serve St. Louis since its earliest days as a main base for Missouri but did not develop it as a hub for connecting services.

Trans World Airlines ( TWA ) took a different approach. This airline was formed in 1930 and its initial routes were transcontinental from New York to Los Angeles with several stops – including at St Louis.

Its hubs and bases changed over the years, along with routes, operations, and technical needs for aircraft to stop. Kansas City soon developed as a main hub (and airline headquarters) in Missouri. Other hubs included Chicago O’Hare, Pittsburgh, New York JFK, and Atlanta.

In this guide, we cover the history of Ozark Air Lines, which merged with TWA in 1986.

In 1994, the base had become so important that TWA moved its headquarters to St. Louis.

American Airlines acquired TWA in 2001

Following financial difficulties. TWA was acquired by American Airlines in April 2001. Fittingly, its ceremonial final flight was on December 1st 2001, from Kansas City to St. Louis.

At the time of the acquisition, St Louis was the main hub for TWA's largely domestic network. It was also still the airline’s headquarters.

American Airlines thus took on St Louis as a major hub. It soon started to reduce this, however, especially as it already operated a hub at nearby Chicago O'Hare. St Louis soon became more of a regional hub for the airline, with Chicago taking on longer services. It also played a role as a reliever hub for other busy hub locations (including Chicago).

Want answers to more key questions in aviation? Check out the rest of our guides here .

Decline of STL as a hub – September 11th attacks

The terrorist attacks in the US on September 11th changed a lot in aviation. Travel demand in the US decreased significantly following the attacks, and with this the need for St Louis to act as a reliever hub for other locations decreased.

At this time, the airline shifted many flights to its larger hub locations of Dallas Fort Worth and Chicago O'Hare, and St Louis never came back to what it was.

Decline of STL as a hub – opening up of other airports

Around the same time, St Louis was dealt another blow to its hub role. A major reason why it still operated as a reliever hub was the presence of slot restrictions at Chicago O'Hare. The government relaxed these in July 2002, removing the previous restriction of 155 flights per hour. This allowed American to transfer more flights away from St Louis.

Ending its hub rule by 2009

Following on from the general decline in travel, and the expansion and shift to O’Hare, traffic volumes fell quickly at St Louis.

In 2009, American Airlines announced it would end St Louis’ role as a hub. This saw flights cut from 200 a day to just 36.

The rise of a new hub for Southwest Airlines

The drop as a hub was significant for American Airlines' history and operations, but it was not all bad for the airport. Almost immediately after American announced it was dropping the airport as a hub location, Southwest Airlines increased service.

By mid 2010, Southwest was flying 83 daily flights and was the largest carrier at St Louis (as reported by the website Airline Geeks ). Service has steadily increased since then and the airline is now by far the dominant operator at the airport.

According to US Bureau of Transportation statistics, it carried almost 65% of passengers for the year to August 2024. American Airlines comes in a distant second place with just under 11% (followed by Delta Air Lines with just under 9% and United Airlines with just over 4%).

Southwest operates a model with several main locations. St Louis may have grown in importance over the past years, but it is far from the airline's busiest hub. In a snapshot analysis in June 2024, Simple Flying showed that it was the tenth busiest US hub for the airline. With 253 average daily roundtrip flights, it was some way behind the leading hubs of Denver (with 591 roundtrip flights), Las Vegas (with 481), and Chicago Midway (with 473).

It is the largest airline at eight of them.

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